Hair follicle stem cell differentiation is inhibited through cross-talk between Wnt/β-catenin and androgen signalling in dermal papilla cells from patients with androgenetic alopecia

Background Hair follicle (HF) regeneration begins when signals from the mesenchyme-derived dermal papilla cells (DPC) reach multipotent epidermal stem cells in the bulge region. Wnt/β-catenin signalling is known to affect mammalian hair growth positively. In androgenetic alopecia (AGA), androgens ca...

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Bibliographic Details
Authors: Leiros, Gustavo Jose, Attorresi, Alejandra Inés, Balaña, Maria Eugenia
Format: article
Status:Published version
Publication Date:2012
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/67895
Online Access:http://hdl.handle.net/11336/67895
Access Level:Open access
Keyword:Dermal Papilla
Hair Follicle Stem Cells
Androgens
Wnt/ Beta Catenin Signalling Pathway
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Description
Summary:Background Hair follicle (HF) regeneration begins when signals from the mesenchyme-derived dermal papilla cells (DPC) reach multipotent epidermal stem cells in the bulge region. Wnt/β-catenin signalling is known to affect mammalian hair growth positively. In androgenetic alopecia (AGA), androgens cause HF miniaturization through a mechanism that remains unclear. Circulating androgens act on DPC and alter paracrine factors that influence hair epithelial cells. Objectives To elucidate the role of androgens in dermal papilla-induced differentiation of HF stem cells. Methods HF stem cell differentiation was evaluated in a coculture model with DPC or culturing with media conditioned by DPC after activation of androgen and Wnt/β-catenin signalling pathways. To study the molecular cross-talk between the androgen and Wnt signalling pathway in DPC, we analysed the expression and activation of downstream Wnt signalling molecules in the presence of androgens. Results In a coculture model with human DPC from patients with AGA and HF stem cells, we observed that androgens abrogate hair differentiation evaluated by hair-specific keratin 6 expression. Wnt signalling activation restored the ability of androgen-treated DPC to induce differentiation. Androgen treatment revealed a significant decrease in the cytoplasmic/total β-catenin protein ratio and upregulation of the activity of glycogen synthase kinase-3β in DPC, indicative of canonical Wnt pathway inhibition. Conclusions These results suggest that androgens deregulate DPC-secreted factors involved in normal HF stem cell differentiation via the inhibition of the canonical Wnt signalling pathway. © 2012 The Authors. BJD © 2012 British Association of Dermatologists.